The design of organometallic catalysts is crucial in the development of catalytic reactions. Herein, we describe a heterometallic [Os-Cu] complex with the characteristics of bimetallics, metallaaromatics, and pincer complexes. This complex serves as a highly effective catalyst for selective amino-and oxyselenation of unactivated alkenes. More than 80 examples including challenging substrates of unsymmetric aliphatic alkenes and amine-based nucleophiles in such reactions are provided. These reactions produce 1,2-difunctionalized products with good yields and high levels of chemo-, regio-, and stereoselectivity. Our studies revealed the following: (i) The usually inert osmium center activates the N-or O-centered nucleophiles. (ii) The copper−osmium bonding and its cooperative effects play essential roles in control the selectivity by bringing the reaction components into close proximity. (iii) The metallaaromatic moiety helps to stabilize the intermediate. These findings provide a versatile platform for catalyst design based on metal−metallaaromatic cooperative effects that have not been attained previously with bimetallic complexes.
The structural design and tuning of properties of metallaaromatics are crucial in materials and energy science. Herein, we describe the rapid synthesis of tetracyclic metallaaromatics containing quinoline and pentalene motifs fused by a metal-bridged fragment. These unique compounds display remarkably broad absorption, enabling for the first time the absorption of metallaaromatics to reach the second near-infrared (NIR-II) bio-window. The formation of osmaquinoline unit involves an unconventional C(sp 2 )À C(sp 3 ) coupling promoted by AgBF 4 to achieve [3+3] cycloaddition. The introduction of cyclic d π -p π conjugation and extension of the aromatic π-framework can effectively shrink the HOMO-LUMO gap, thus broadening the absorption window. The considerable photothermal conversion efficiency (PCE) in both the NIR-I and NIR-II windows, the high photothermal stability and the excellent electrochemical behavior suggest many potential applications of these condensed metallaquinolines.
The traditional technologies for industrial and agricultural effluent treatment are often energy‐intensive. Herein, we suggest an electrochemical redox strategy for spontaneous and simultaneous decontamination of wastewater and generation of both fuels and electricity at low cost. Using hydrazine and nitrate effluents as a demonstration, we propose a hydrazine‐nitrate flow battery (HNFB) that can efficiently purify the wastewater and meanwhile generate both ammonia fuel and electricity with the assistance of our developed bimetallic RuCo precatalyst. Specifically, the battery delivers a peak power density of 12 mW cm−2 and continuously operates for 20 h with an ammonia yield rate of ca. 0.38 mmol h−1 cm−2 under 100 mA cm−2. The generated electricity can further drive a hydrazine electrolyzer to produce hydrogen fuel. Our work provides an alternative pathway to purify wastewater and generate high value‐added fuels at low cost.
Electrophilic aromatic substitution (EAS) reactions are widely regarded as characteristic reactions of aromatic species, but no comparable reaction has been reported for molecules with Craig-Möbius aromaticity. Here, we demonstrate successful EAS reactions of Craig-Möbius aromatics, osmapentalenes, and fused osmapentalenes. The highly reactive nature of osmapentalene makes it susceptible to electrophilic attack by halogens, thus osmapentalene, osmafuran-fused osmapentalene, and osmabenzene-fused osmapentalene can undergo typical EAS reactions. In addition, the selective formation of a series of halogen substituted metalla-aromatics via EAS reactions has revealed an unprecedented approach to otherwise elusive compounds such as the unsaturated cyclic chlorirenium ions. Density functional theory calculations were conducted to study the electronic effect on the regioselectivity of the EAS reactions.
The traditional technologies for industrial and agricultural effluent treatment are often energy‐intensive. Herein, we suggest an electrochemical redox strategy for spontaneous and simultaneous decontamination of wastewater and generation of both fuels and electricity at low cost. Using hydrazine and nitrate effluents as a demonstration, we propose a hydrazine‐nitrate flow battery (HNFB) that can efficiently purify the wastewater and meanwhile generate both ammonia fuel and electricity with the assistance of our developed bimetallic RuCo precatalyst. Specifically, the battery delivers a peak power density of 12 mW cm−2 and continuously operates for 20 h with an ammonia yield rate of ca. 0.38 mmol h−1 cm−2 under 100 mA cm−2. The generated electricity can further drive a hydrazine electrolyzer to produce hydrogen fuel. Our work provides an alternative pathway to purify wastewater and generate high value‐added fuels at low cost.
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